Watch cases are known formed preferably of precious metal (gold or platinum) the caseband of which is hollowed out on the interior in order to achieve a substantial economy of precious material and thus to allow a lower selling price than could be permitted if such caseband were solid.
Patent document CH-A-664 251 describes a watch case of gold in which the movement is fixed to the caseband-bezel which is hollowed out on the interior. Such fastening is obtained through a fitting piece which is centered by the interior. To this end an axial projection from the fitting piece is loosely fitted around a corresponding projection which is fixed to the case and which is constituted by a portion of a flange another part of which is squeezed between an internal lip of the caseband bezel and the crystal. The axial securing of the fitting piece is assured by a latching bolt which bears against the shoulder of the caseband and maintains the fitting piece supported under the lip.
Patent document EO-A-0 379 974 (=U.S. Pat. No. 4,970,708) also describes a watch case including a hollowed-out caseband in vault form. Such caseband includes first and second cylindrical support surfaces cooperating respectively with a crystal and a back cover. Three studs fixed to the caseband are arranged within the space defined by the vault-formed hollow. Each of the studs bears a projection extending towards the movement and borne by the case, said projection bearing an upper snap on which rests a flange against which the crystal is supported, and a lower snap on which rests a casing ring against which the back cover bears.
The hollowed-out casebands described in the documents cited hereinabove are fragile in the sense that they are sensitive to lateral shocks applied to the watch, the extreme thinness of the wall of the caseband explaining why this latter may be dented by the slightest blow thereagainst.
Resistance to shock has been improved by arranging ribs within the caseband as within the interior of the back cover as such is seen in patent document EP-A-O 378 125 (=U.S. Pat. No. 4,995,023). If improvements have been brought about in respect of the deforming of the caseband due to traction by the bracelet, such improvements are however minimum as to shock resistance, such caseband being easily dented because of its very small thickness (on the order of 0.15 mm).
It is noted in other respects that cases obtained according to the patents cited hereinabove give such an impression of lightness that one can be placed in doubt as to whether they are formed of gold. As it is not authorized to add weight which would be present only with the sole purpose of inducing belief in the presence of solid gold with neither function nor real utility for the constitution or the operation of the watch, the present invention imagines filling almost entirely the hollow of the caseband made of gold by a circle, preferably made of brass, such circle fulfilling two functions: that of a casing ring support for the movement and coupling of this latter with the caseband and that of reinforcement of the caseband for rendering it resistant to shocks, since behind the caseband made of thin gold is found said ring which renders the caseband subject to denting only with difficulty. It will be understood that additionally such ring makes the watch heavier.